Indonesia Stock Exchange Overhauls Market Rules, Purging 300 Closely Held Stocks from Benchmark Index

JAKARTA, Investortrust.id — The Indonesia Stock Exchange (IDX) is launching one of its most sweeping structural cleanups in years, expanding its High Shareholding Concentration (HSC) watchlist more than fourfold to 383 companies and stripping 300 newly flagged stocks from the benchmark Jakarta Composite Index (IHSG) effective Friday, November 13, 2026.

The aggressive overhaul, compiled jointly with the Indonesian Central Securities Depository (KSEI) based on shareholder registries as of October 30, targets thinly traded, tightly controlled equities that have long distorted index movements and fueled global investor concerns over market integrity. By removing the 300 newly identified stocks—which represent roughly 6.16% of total IHSG market capitalization—regulators aim to ensure that Indonesia's flagship equity gauge accurately reflects genuinely investable, liquid companies.

Scrapping Market-Cap Filters to Capture the Entire Bourse

Under the revised screening methodology unveiled by IDX President Director Jeffrey Hendrik, the exchange eliminated two major loopholes that previously shielded smaller or less active companies from scrutiny. Regulators abolished the Rp 5 trillion minimum market capitalization threshold as well as the price-impact ratio (PIR) requirement, applying the concentration screen universally across every listed firm on the bourse.

"The HSC methodology that previously calculated a threshold of stocks above Rp 5 trillion in market capitalization as its universe is no longer used. That means screening for HSC is conducted across the entire market, or all stocks listed on the Indonesia Stock Exchange," Jeffrey said during a press conference at the IDX building in Jakarta on Tuesday. Removing the PIR criterion also allows regulators to flag concentrated ownership structures proactively rather than waiting for anomalous trading swings. "That means we do not wait until there is a stock price movement," he added.

Under the tightened rule, any listed issuer where 10 or fewer shareholders—combining scripless and scrip holdings—control at least 92.5% of total shares is automatically designated as an HSC stock. While the exchange emphasized that inclusion on the watchlist does not indicate corporate wrongdoing or rule violations, the removal of 300 firms from the IHSG calculation strips them of passive benchmark weightings. "Of course we hope to announce it as soon as possible. Hopefully tomorrow those 300 HSC stocks can be announced, and on Friday they can already exit the IHSG calculation," Jeffrey told reporters on Wednesday.

To reinforce institutional credibility behind the crackdown, the exchange also streamlined its advisory HSC Committee from nine members to seven while preserving an independent majority. The reconstituted panel pairs three self-regulatory organization (SRO) chiefs—IDX's Jeffrey Hendrik, KSEI President Director Samsul Hidayat, and Indonesian Clearing and Guarantee Corporation (KPEI) President Director Antonius Herman Azwar—with four independent figures, namely National Committee on Governance Policy Chairman Mardiasmo, Mandiri Sekuritas President Director Alex Widi, academic Eduardus Tandelilin, and Capital Group's F. Chapman Taylor. "The HSC Committee met and decided that to improve the credibility and governance of both the committee's decision-making process and its output, its credibility needed to be safeguarded and enhanced," Jeffrey said.

Major Conglomerate Affiliates Dominate the Watchlist

The removal of market-cap barriers swept dozens of prominent companies linked to Indonesia's wealthiest business dynasties onto the expanded 383-stock register. The Salim Group, led by tycoon Anthoni Salim, accounted for one of the largest clusters with eight affiliated issuers, including PT Indoritel Makmur Internasional Tbk (DNET) at 98.057% concentration, PT Indomobil Sukses Internasional Tbk (IMAS) at 95.484%, PT Indomobil Multi Jasa Tbk (IMJS) at 94.879%, PT Nippon Indosari Corpindo Tbk (ROTI) at 97.048%, PT Fast Food Indonesia Tbk (FAST) at 93.528%, and PT Bank Ina Perdana Tbk (BINA) at 94.113%. Two major ventures co-linked with Salim—property developer PT Pantai Indah Kapuk Dua Tbk (PANI) alongside Sugianto Kusuma, and data center operator PT DCI Indonesia Tbk (DCII) alongside Otto Toto Sugiri—also made the list at 95.057% and 99.960%, respectively.

The Widjaja family's Sinar Mas Group followed closely with seven listed entities, spanning PT Duta Pertiwi Tbk (DUTI) at 99.879%, PT Sinar Mas Agro Resources and Technology Tbk (SMAR) at 99.560%, PT Golden Energy Mines Tbk (GEMS) at 99.239%, PT MSIG Life Insurance Indonesia Tbk (LIFE) at 99.150%, PT Ekamas Mora Republik (MORA) at 95.652%, PT Dian Swastatika Sentosa Tbk (DSSA) at 93.221%, and PT Pabrik Kertas Tjiwi Kimia Tbk (TKIM) at 92.626%. Similarly, Dato Sri Tahir's Mayapada Group recorded three entries—PT Maha Properti Indonesia Tbk (MPRO) at 99.993%, PT Sejahteraraya Anugrahjaya Tbk (SRAJ) at 98.834%, and PT Bank Mayapada Internasional Tbk (MAYA) at 96.715%—while the Riady family's Lippo Group saw five affiliates flagged, led by PT Multipolar Technology Tbk (MLPT) at 99.406% and PT Lippo General Insurance Tbk (LPGI) at 99.278%.

Other major business groups appearing across the register include the Hartono family's Djarum Group via PT Solusi Tunas Pratama Tbk (SUPR) at 99.979%, PT Supra Boga Lestari Tbk (RANC) at 98.087%, and PT Global Digital Niaga Tbk (BELI) at 93.834%; Prajogo Pangestu's Barito Group through PT Barito Renewables Energy Tbk (BREN) at 96.693% and PT Chandra Daya Investasi Tbk (CDIA) at 94.304%; and Low Tuck Kwong's coal empire anchored by PT Bayan Resources Tbk (BYAN) at 96.500%. Affiliates tied to Saratoga, the Harita Group, Haji Isam's Jhonlin Group, Hermanto Tanoko's Tancorp, the Bakrie Group, and retail giant MAP also populated the list.

Responding to the inclusion of Saratoga-linked entities on the watchlist, PT Saratoga Investama Sedaya Tbk (SRTG) shareholder Sandiaga Salahuddin Uno deferred operational questions to the firm’s management while voicing confidence in Indonesia’s broader economic trajectory and governance reforms. Sandiaga, who co-founded the investment firm with Edwin Soeryadjaya and holds a 21.5189% stake—equivalent to 2.92 billion shares—alongside Saratoga's 92.706% concentration and affiliate PT Provident Investasi Bersama Tbk (PALM) at 98.293%, noted that he no longer holds an active executive or board role at the company. "Maybe for Saratoga, it is best to ask Saratoga's management directly, because I am no longer active there, but we are optimistic about the Indonesian economy," Sandiaga told Investortrust.id at the IDX building in Jakarta on Thursday.

Sandiaga emphasized that strengthening corporate transparency and governance remains critical to capitalizing on improving market sentiment. "We are optimistic about our economic fundamentals; we will continue to enhance transparency and also ensure good governance for the companies being managed, and we must use today's improvement momentum going forward," he said. Pointing to macroeconomic resilience, he added that domestic expansion continues to be anchored by steady output, employment gains, and capital inflows. "Because if we look from the side of our economic growth, it is still positive, from job growth metrics, investment entering Indonesia, so overall I am optimistic," Sandiaga said.

Analysts Urge Portfolio Discipline Over Panic Selling

Market strategists cautioned retail investors to reassess liquidity risks in their portfolios following the expansion, while advising against indiscriminate selling. Capital market observer Elandry Pratama warned that tighter free floats leave concentrated stocks vulnerable to sharper price swings, though he stressed that an HSC label does not reflect deteriorating corporate earnings.

"In my view, the increase in the number of HSC stocks from 83 to 383 needs to be watched closely by retail investors, because it has the potential to increase volatility and liquidity pressure on the stocks included in the list," Elandry said on Wednesday. "So, the focus is not merely on salvaging a portfolio, but on improving asset quality so that it is more resilient against market volatility and still holds long-term growth potential."

PT Mirae Asset Sekuritas Indonesia Senior Technical Analyst Muhammad Nafan Aji noted that narrow public share distribution can trap retail traders during market downturns and diminish institutional appetite once stocks exit the IHSG benchmark. "As a result, retail investors may face wider bid-offer spreads and difficulty selling shares in large quantities when selling pressure increases," Nafan said, urging market participants to rotate toward liquid companies with sound fundamentals. "Focus on issuers that have healthy financial performance, positive cash flow, sustainable earnings growth, good corporate governance, and adequate trading liquidity."